1. Field of the Invention
The present invention relates to an injection molding machine and, more particularly, to a heating cylinder protection cover of the injection molding machine.
2. Description of the Related Art
An electric heater is set in a heating cylinder of an injection molding machine, and supplies a heat quantity necessary for melting resin. The supply of the heat quantity is performed by heat conduction due to direct contact of the electric heater and the heating cylinder, whereby the heating cylinder is warmed. Therefore, a heating cylinder protection cover that prevents the body of an operator from coming into direct contact with the electric heater and the heating cylinder having high temperature is attached to the injection molding machine.
Japanese Patent Application Laid-Open No. 2012-6276 discloses that the outer side of a heating cylinder is surrounded by a double cover of a heat retaining cover and a heat insulating cover on the outer side of the heat retaining cover. One end of a heat retaining cover attaching section is joined to a heat retaining cover inclined section that joins the heat retaining cover to the heating cylinder. A heating insulating cover attaching section is formed in a heating insulating cover vertical surface section that joins the heat insulating cover to the heat retaining cover. The heat insulating cover attaching section is arranged in a position lower than the heat retaining cover attaching section.
A power supply cable of a heating cylinder electric heater is sometimes set on the inner side of a heating cylinder protection cover that covers the entire circumference of the heating cylinder. The inner side of the heating cylinder protection cover, which covers the entire circumference of the heating cylinder, has high temperature because heat accumulates on the inner side. This is undesirable as an environment of use of the power supply cable of the heating cylinder electric heater. However, when the heating cylinder protection cover is cut wide in order to draw out the power supply cable of the electric heater to the outer side of the heating cylinder, the heating cylinder is dangerously exposed from the cut part.
In general, a plurality of the electric heaters for the heating cylinder are used in the heating cylinder. The power supply cables of the respective electric heaters are bundled into one cable by a tying band or the like. Therefore, it is difficult in terms of structure to draw out only the power supply cables of the electric heaters for the heating cylinder to the outer side of the heating cylinder protection cover without untying the power supply cables.
The cover disclosed in Japanese Patent Application Laid-Open No. 2012-6276 has structure in which the heat of the heating cylinder is not easily transferred to the heat insulating cover. The cover does not particularly improve the environment of use of the power supply cable of the heating cylinder electric heater.